McKenzie Pass, geology
August 17, 2005
This was the second year for this geological trip, and the summer
heat wave dropped just enough to make it near ideal weather.
Seven of us started from Eugene, and an eighth, who had signed up by email, met us on the McKenzie Highway.
As before, we started the geological tour at the junction of Highways
126 and 242 with an introduction to the geological history of the area.
We then drove up the McKenzie Pass road, stopping several times to
view, examine, and discuss the volcanic features and evidence of
The first stop was for a view of the canyon walls of Lost Creek and a
discussion of the glacier that had filled the valley.
This was followed by a hike to Proxy Falls, over lava flows from
After lunch we walked over a small part of the lava flow from South
Belknap Crater, examined glacial grooves cut into older volcanic rock
by Craig Lake, walked across an “island” of the older
volcanic rock nearly engulfed by young lava from Little Belknap Crater,
hiked a short way on the Little Belknap lava and examined the contact
between the younger flow from Little Belknap Crater and the older flow
from Yapoah Crater, had a clear but windy view of the peaks from atop
Dee Wright Observatory, and, finally walked the loop trail on the Yapoah
From McKenzie Pass we drove straight back to Eugene.
Peter Rodda (leader).